Answer:
70
Explanation:
On Tuesday, the balance in your bank account is $40.
Since from Wednesday to Friday you withdraw $10 a day, keep adding $10 to each day.
On Wednesday the balance is $40 + $10 = $50
On Thursday the balance is $50 + $10 = $60
On Friday the balance is $60 + $10 = $70
The balance in your bank account at the end of the day on Friday is $70